James Parker came out at age 17 and later entered into a relationship with another man. He worked as a gay activist for a while, but his personal experiences of intimacy and human sexuality eventually led him to grasp that “same-sex marriage just doesn’t exist; even if you want to say that it does.” He concluded that trying to persuade those with homosexual inclinations that they can have marriage like heterosexual couples is basically to “hoodwink” them: “Deep down, there is no mystery between two men, ultimately.“

This striking insight helps bring into focus the authentic and remarkable mystery we encounter in the joining of husband and wife in marriage. That abiding mystery touches on their one- flesh union and reveals an inner fruitfulness, enabling them to contribute together something greater than either can do alone, namely, the engendering of new life in the marital embrace.

Ultimately, that life-giving mystery flows from their radical male–female complementarity.

St. John Paul II commented on this “mystery of complementarity” when he noted how “uniting with each other [in the conjugal act] so closely as to become ‘one flesh,’ man and woman, rediscover, so to speak, every time and in a special way, the mystery of creation.”

The personal and bodily complementarity of man and woman, along with the “duality of a mysterious mutual attraction,” reminds us, again in the words of the pope, how “femininity finds itself, in a sense, in the presence of masculinity, while masculinity is confirmed through femininity.”

In recent times, nevertheless, the importance of the bodily and spiritual complementarity of man and woman has come to be diminished and even negated in the minds of many, largely due to the diffusion of contraception. This way of intentionally impeding our own procreativity has effectively diminished and even undermined our ability to perceive the inner order and interpersonal meaning of our own sexuality. St. John Paul II once described the root truth about human sexuality as that “characteristic of man — male and female —which permits them, when they become ‘one flesh,’ to submit at the same time their whole humanity to the blessing of fertility.”

The routine promotion of contraceptive sexual relations across all strata of society has effectively collapsed the mystery of sexuality into the trivial pursuit of mutually-agreed-upon pleasurable sensations. It has managed to reconfigure that sexuality into, basically, sterile acts of mutual auto-eroticism. Men and women, neutered and neutralized by various surgeries, pharmaceuticals or other devices, no longer really need each other in their complementary sexual roles, with homosexual genital activity claiming the status of just another variant of the same game. This depleted vision of our sexuality strips out the beautiful mystery at its core and diminishes our human dignity.

Human sexuality clearly touches deep human chords, including the reality of our solitude. In the depths of the human heart is found a desire for completion through the total spousal gift of oneself to another, a gift that profoundly contributes to alleviating our primordial sense of human solitude. Both St. John Paul II and Pope Francis have noted how the deeper mystery of communion that we seek through intimacy is connected to this desire to overcome solitude. We are ultimately intended for communion, so our experiences of human solitude draw us into relationship, and beckon us to an encounter with the other.

Yet the union of friendship that arises between two men, for example, or between two women, while clearly important in helping to overcome solitude, can be predicated only on non-genital forms of sharing if their friendship is to be authentic, fruitful and spiritually life-giving. Genital sexual activity between members of the same sex fails to communicate objectively either the gift of life or the gift of self. Such activity countermands authentic intimacy by collapsing into a form of consensual bodily exploitation, contradicting the very design and meaning of the body in its nature as masculine or feminine. It represents, in fact, the lifeless antithesis of nuptial fruitfulness and faithfulness.

The beauty and meaning of every sexual encounter in marriage, then, is rooted not only in faithful and exclusive love, but also in the radical complementarity of spouses manifested in the abiding mystery of their mutual procreativity.

Father Pacholczyk earned his doctorate in neuroscience from Yale and did post-doctoral work at Harvard. He is a priest of the Diocese of Fall River, Massachusetts, and serves as the director of education at The National Catholic Bioethics Center in Philadelphia.